A simple "?" button in the top-right corner that, once clicked, would allow you to click any element for a short explanation of its effects. Click the "?", then click the button that looks like ((+)), and it'll tell you that this is your "Heal Crew" power, generated by manning the Healing Room.

The downside to this is that it WOULD highlight the incredibly unfinished state of the game - click the Engine Room, and it would have to say "This is the Engine Room - it currently serves no unique or appropriate purpose, just a tacked-on placeholder mechanic which duplicates that of the Bridge."